Exam prompt
How do mass number and proton number change in alpha decay?
How certain was your answer?
CorrectUnsureWrong
AI · FSRS-6 · Cited sources
Compare six
flashcard apps
for STEM workflows
Compare Quanta, Anki, Quizlet, RemNote, Knowt and Brainscape by scheduler, card generation, source status, STEM notation, offline use and pricing.
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Physics · Radioactivity
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„Ich hab schon einige Karteikarten-Apps ausprobiert und Quanta hat mir bis jetzt am besten gefallen. […] Auch die Multiple Choice - Funktion und Prüfungssimulation helfen mir echt weiter."- TU Dresden
- Humboldt-Universität zu Berlin
- HTW Dresden
- Fachhochschule Dresden
- Universität Leipzig
- HTWK Leipzig
- Freie Universität Berlin
- IU Internationale Hochschule
- FernUniversität in Hagen
What is the best flashcard app in 2026?
There is no single best flashcard app for everyone. Anki leads on open source and offline use, Quizlet on its large set library. For STEM, Quanta combines AI card generation, FSRS-6 native spaced repetition and a source citation on every AI card. Quanta Starter is free forever.
Why I built another flashcard app
“Anki, Quizlet and RemNote earned their place. Anki made spaced repetition free and open for millions, Quizlet made study sets effortless to share, and RemNote tied notes and cards together. I am not here to talk any of that down. What I wanted was different: FSRS-6 with personal intervals after the first rating, AI cards generated from my own PDF, and a source status attached to Source-First cards so I can trace them. On a STEM exam, a card that quietly invented a constant is worse than no card at all. So Quanta makes the source and verification status visible instead of presenting every AI card as equally verified.”
0.3460
log-loss of FSRS-6, lower is better
srs-benchmark (formerly fsrs-benchmark), open-spaced-repetition, retrieved 5 September 2026
12.6%
improvement over the state of the art
Ye et al. 2022, ACM SIGKDD, on 220 million behaviour logs
about 80%
of the vocabulary pairs recalled after one week with repeated retrieval
versus 36% and 33% without further retrieval (Karpicke & Roediger 2008, Science 319:966–968)
€0
Quanta Starter, free forever
Essential from €9.75/mo
How to choose a flashcard app in 2026
Five criteria that actually separate these apps, each with a short, factual verdict.
AI card generation from your own material
An AI flashcard app should turn your notes, PDFs or a topic prompt into question-answer cards, not just store cards you type by hand. Quanta, Quizlet, RemNote and Knowt all ship an AI generator. Anki and Brainscape have no built-in generator, so cards come from manual entry or shared decks (as of June 2026).
Verdict: If you want cards built from your script, choose an app with a native AI generator. If you prefer to author every card yourself, Anki and Brainscape keep you fully in control.
Spaced repetition algorithm (FSRS-6 vs SM-2)
The scheduler decides when each card comes back. FSRS-6 models stability, difficulty and retrievability per card. Current Anki versions support FSRS alongside legacy scheduling; Quanta uses FSRS-6 and starts personal intervals after the first rating. In the open comparison run by the open-spaced-repetition community, FSRS-6 reaches a log-loss of 0.3460 on 349,923,850 reviews from 9,999 collections (retrieved on 5 September 2026); log-loss measures prediction error, lower is better, and that table carries no row for SM-2. The peer-reviewed paper behind it, Ye et al. 2022, reports 220 million behaviour logs and a 12.6% improvement over the state of the art. Both are results of those datasets, not a blanket product effect. None of it compares Quanta with the current Anki app.
Verdict: Both Quanta and current Anki support FSRS. Quanta provides a guided FSRS-6 workflow; Anki offers FSRS and legacy scheduling with more configuration choices.
Per-card source citation (anti-hallucination)
AI-generated cards can hallucinate. In Quanta's Source-First path, cards carry a source status. PDF generation is bound to the uploaded document; where text is extractable, a quote match can verify the evidence, while unmatched visual cards remain transparently unverified. If no suitable source is found, no flashcards are created; a file or a URL is the way. Among the apps compared here, Anki, Quizlet, RemNote, Knowt and Brainscape do not document a comparable per-card source-status workflow (as of June 2026).
Verdict: If you study from a fixed source and need to trace a claim back to its text, source status is a useful criterion. A citation shows text binding, not that the source itself is factually correct.
STEM rendering: LaTeX and chemistry
Math, physics and chemistry need formula support. Quanta renders LaTeX natively with a live preview on all platforms and draws SMILES structures for chemistry. Anki supports MathJax, Quizlet and Knowt handle basic equations, RemNote renders LaTeX. Native chemistry structure rendering is uncommon across the set.
Verdict: For math-heavy or chemistry-heavy subjects, native LaTeX and structure rendering save real time. For pure vocabulary or fact recall, any of these apps is sufficient.
Exam features and price
Beyond review, some apps add exam preparation. Quanta includes an exam simulation and a Readiness Score that estimates how prepared you are for a set date from your FSRS retention data (an estimate, not a guarantee). Quanta Starter is free forever; Essential starts at €9.75/mo billed annually. Anki desktop and Android are free; AnkiMobile for iPhone is a one-time $24.99 (US App Store, as of July 2026).
Verdict: If you study toward a fixed exam date, the Readiness Score and exam simulation are differentiators. For open-ended review, a free tier on any of these apps will do.
Flashcard apps compared, feature by feature
A factual matrix. Algorithm data is peer-reviewed (Ye et al. 2022).
| Criterion | Quanta | Anki | Quizlet | RemNote | Knowt | Brainscape |
|---|---|---|---|---|---|---|
| AI card generation from PDF | Yes | No | Yes | Yes | Yes | No |
| FSRS support | Yes | Yes | No | Yes | No | No |
| Scheduler family | FSRS-6 | FSRS + legacy | Proprietary | FSRS | Proprietary | Proprietary |
| Source status for Source-First AI cards | Yes | No | No | No | No | No |
| Native LaTeX | Yes | MathJax | Basic | Yes | Basic | No |
| Chemistry structures (SMILES) | Yes | No | No | No | No | No |
| Exam simulation | Yes | No | No | No | Yes | No |
| Readiness Score | Yes | No | No | No | No | No |
| Anki import (.apkg) | Yes | Yes | No | Yes | Yes | No |
| Free tier | Yes | Yes | Yes | Yes | Yes | Yes |
| Open source | No | Yes | No | No | No | No |
| Full offline mode | Partial | Yes | Partial | Partial | Partial | Partial |
Log-loss data: Ye et al. 2022, ACM SIGKDD, doi:10.1145/3534678.3539081. Features and prices as of June 2026. Price comparison
Pros and cons, honestly
No app is the best choice for everything. Here are the strengths and weaknesses of each, including our own.
Quanta
Strengths
- FSRS-6 scheduling with personal intervals after the first rating
- Per-card source status for Source-First AI cards
- AI card generation from PDF, photo and topic prompt
- Native LaTeX and SMILES, plus exam simulation and Readiness Score
- STEM focus (math, physics, chemistry, biology, computer science)
- Starter free forever, including on iPhone (PWA, no app-store fee)
Weaknesses
- No plugin ecosystem, so the feature set is limited to what ships natively
- Full offline mode is only partial (PWA cache); Anki is more mature here
- Not open source, unlike Anki
- Younger than Anki and Quizlet, so a smaller library of shared decks
Anki
Strengths
- FSRS integrated in current versions alongside legacy scheduling
- Large plugin ecosystem for almost any use case
- Fully offline on desktop and Android
- Open source, with free desktop and Android apps
- Very large community library of shared decks
Weaknesses
- FSRS and legacy scheduling options add configuration decisions
- No built-in AI card generator (as of June 2026)
- AnkiMobile for iPhone is a one-time $24.99
- Steeper learning curve than most apps in this list
Quizlet
Strengths
- Very large library of user-created study sets
- AI features and multiple study modes (Learn, Test, Match)
- Familiar, beginner-friendly interface across web and mobile
- Strong for vocabulary and language learning
Weaknesses
- Uses a proprietary scheduler, not FSRS-6
- Several study modes sit behind Quizlet Plus (as of June 2026)
- No per-card source citation for AI-generated content
- Limited native support for advanced STEM notation
RemNote
Strengths
- Notes and flashcards in one connected workspace
- FSRS-based scheduling
- LaTeX support for math and science
- Strong for building cards directly from outlined notes
Weaknesses
- Note-plus-flashcard model has a learning curve
- No per-card source citation for AI-generated cards
- No chemistry structure rendering
- Advanced features and higher limits require a paid plan
Knowt
Strengths
- Free AI generation from notes and uploaded files
- Imports existing Quizlet sets
- Practice tests and multiple study modes
- Generous free tier
Weaknesses
- Uses a proprietary scheduler, not FSRS-6
- No per-card source citation for AI-generated cards
- Limited native support for advanced STEM notation
- Smaller, newer ecosystem than Anki or Quizlet
Brainscape
Strengths
- Confidence-based repetition with a simple 1-to-5 rating
- Curated, expert-made card collections
- Clean, focused study interface
- Web and mobile apps with sync
Weaknesses
- No built-in AI card generator
- Proprietary scheduler, not FSRS-6
- No per-card source citation
- Most curated content and features require a subscription
The science behind FSRS-6 and active recall
In the open comparison run by the open-spaced-repetition community, FSRS-6 reaches a log-loss of 0.3460 on 349,923,850 reviews from 9,999 collections (retrieved on 5 September 2026); log-loss measures prediction error, lower is better, and that table carries no row for SM-2. The peer-reviewed paper behind it, Ye et al. 2022, reports 220 million behaviour logs and a 12.6% improvement over the state of the art. Both are results of those datasets, not a blanket product effect. None of it compares Quanta with the current Anki app. Karpicke and Roediger (2008) report about 80% of the vocabulary pairs recalled after one week in the two conditions with repeated retrieval practice, and 36% and 33% in the two conditions where pairs were dropped from further testing once recalled; those figures describe that experiment and are not a general promise for every learning situation or for Quanta. These studies test the methods, not Quanta itself.
Sources: srs-benchmark (formerly fsrs-benchmark), open-spaced-repetition, retrieved 5 September 2026 · Ye et al. 2022, ACM SIGKDD, doi:10.1145/3534678.3539081 · Karpicke & Roediger 2008, Science, doi:10.1126/science.1152408
Frequently asked questions
What is the best flashcard app in 2026?
There is no single best flashcard app for everyone. Anki leads on open source, full offline mode and its plugin ecosystem. Quizlet leads on its large set library. For STEM students who want AI card generation, FSRS-6 native and per-card source citation, Quanta is built for that case. The right choice depends on whether you value control and offline use (Anki) or AI generation with cited sources and STEM rendering (Quanta).
Which is the best AI flashcard app?
Quanta, Quizlet, RemNote and Knowt all generate flashcards with AI. In Quanta's Source-First path, cards carry a source status. PDF generation is bound to the uploaded document; where text is extractable, a quote match can verify evidence, while unmatched visual cards remain unverified. If no suitable source is found, no flashcards are created; a file or a URL is the way. If you mainly want a large existing set library, Quizlet or Knowt may fit better.
What is the best spaced repetition app?
Spaced repetition apps differ mainly by scheduler and workflow. Current Anki versions support FSRS alongside legacy scheduling; Quanta and RemNote also use FSRS. In the open comparison run by the open-spaced-repetition community, FSRS-6 reaches a log-loss of 0.3460 on 349,923,850 reviews from 9,999 collections (retrieved on 5 September 2026); log-loss measures prediction error, lower is better, and that table carries no row for SM-2. The peer-reviewed paper behind it, Ye et al. 2022, reports 220 million behaviour logs and a 12.6% improvement over the state of the art. Both are results of those datasets, not a blanket product effect. None of it compares the current Anki app with Quanta. In Quanta, personal FSRS intervals begin after the first rating.
What does the FSRS versus legacy SM-2 study show?
SM-2 was published in 1987 and uses an ease-factor model. FSRS (Free Spaced Repetition Scheduler) goes back to Ye et al. 2022 (ACM SIGKDD, doi:10.1145/3534678.3539081). In the open comparison run by the open-spaced-repetition community, FSRS-6 reaches a log-loss of 0.3460 on 349,923,850 reviews from 9,999 collections (retrieved on 5 September 2026); log-loss measures prediction error, lower is better, and that table carries no row for SM-2. The peer-reviewed paper behind it, Ye et al. 2022, reports 220 million behaviour logs and a 12.6% improvement over the state of the art. Both are results of those datasets, not a blanket product effect. This is an algorithm comparison, not a study of Quanta versus the current Anki app; current Anki versions support FSRS as well as legacy scheduling.
Is there a flashcard app that cites its sources?
Yes. Quanta attaches a source to each AI-generated card through its Quanta Verified protocol: every card stores the source title, type and a confidence score. On a PDF upload, the generator draws only from that document, and cards it cannot ground in the source are dropped server-side. Among the apps compared here, Anki, Quizlet, RemNote, Knowt and Brainscape do not offer per-card source citation for AI content (as of June 2026).
What is the best flashcard app for STEM and medical students?
STEM and medicine need formula and structure support. Quanta renders LaTeX natively with a live preview on all platforms and draws SMILES chemistry structures, and it focuses on math, physics, chemistry, biology and computer science. The AI generator handles textbook PDFs and shows the source for each card. Anki is also widely used in medicine through community decks, though formula support relies on MathJax and there is no built-in AI generator (as of June 2026).
Can I import my Anki decks into a new flashcard app?
It depends on the app. Quanta, RemNote and Knowt can import Anki .apkg files; Quizlet and Brainscape cannot import .apkg directly (as of June 2026). Quanta imports question-and-answer text, not images, audio, media or Anki scheduling history. Imported cards start as new cards, and personal FSRS-6 scheduling begins after the first new rating.
What does Quanta cost compared to other flashcard apps?
Quanta Starter: Free forever: 1 topic, no more than 100 cards in total, FSRS, and exactly one AI generation run over the account lifetime. The regular generator offers 40–100 cards from text, a link, or up to 10 files; the guided onboarding entry offers 10–50 from text or files. The onboarding run counts as that one lifetime run; Starter has no monthly AI quota. Further AI flashcard generations require Essential, which starts at €9.75/mo billed annually (unlimited cards, 300 AI cards per month), with Performance above it. Anki desktop and Android are free; AnkiMobile for iPhone is a one-time $24.99 (US App Store). Quizlet, RemNote, Knowt and Brainscape each offer a free tier with paid upgrades. Quanta runs as a PWA, so the iPhone version is free with no app-store fee (as of July 2026).
Final verdict
As of June 2026, there is no single best flashcard app, only the best fit for your subject and workflow. Choose Anki if open source, full offline mode and a large plugin ecosystem matter most. Choose Quizlet or Knowt for a big existing set library and quick vocabulary study. Choose Quanta if you study STEM and want FSRS-6 native, AI card generation from your own PDF, native LaTeX and chemistry rendering, and a source citation on every AI card. The deciding question is whether you prioritise control and offline use or AI generation with cited sources.
Keep comparing
The numbers behind this page
Three items you can check, with their source next to them.
What retrieval practice was measured to do
Karpicke and Roediger (2008) report about 80% of the vocabulary pairs recalled after one week in the two conditions with repeated retrieval practice, and 36% and 33% in the two conditions where pairs were dropped from further testing once recalled; those figures describe that experiment and are not a general promise for every learning situation or for Quanta. Karpicke, J.D. and Roediger, H.L. (2008). Science, 319(5865), 966 to 968. doi:10.1126/science.1152408
Log-loss 0.3460 in the open comparison
In the open comparison run by the open-spaced-repetition community, FSRS-6 reaches a log-loss of 0.3460 on 349,923,850 reviews from 9,999 collections (retrieved on 5 September 2026); log-loss measures prediction error, lower is better, and that table carries no row for SM-2. The peer-reviewed paper behind it, Ye et al. 2022, reports 220 million behaviour logs and a 12.6% improvement over the state of the art. Both are results of those datasets, not a blanket product effect. It compares schedulers, not the Quanta app with current Anki. srs-benchmark (formerly fsrs-benchmark), open-spaced-repetition, retrieved 5 September 2026, https://github.com/open-spaced-repetition/srs-benchmark · Ye, J. et al. (2022). ACM SIGKDD. doi:10.1145/3534678.3539081
Where your data sits
Accounts, learning content and results are stored in Frankfurt, region europe-west3. AI text functions run through the EU endpoint of Mistral AI SAS in Paris; reading files and voice input runs through the provider standard endpoint, for which no processing location is promised. A data processing agreement with standard contractual clauses applies.
The studies examine the learning method, not this product, and they say nothing about your exam result.